JP2019016488A - Method of treating conductive material - Google Patents

Abstract

To provide a method for treating a conductive material that makes it possible to obtain a conductive material with improved fluctuations in conductivity within an electrode or improved fluctuations in conductivity between electrodes.SOLUTION: A conductive material having a net-like thin metallic wire pattern formed by silver on a support is treated with a surface treatment liquid containing a specific mercaptobenzothiazole compound.SELECTED DRAWING: None

Description

  The present invention relates to a method for treating a conductive material, in which a conductive material with improved conductive flare within an electrode or between conductive electrodes can be obtained.

  In electronic devices such as smartphones, personal digital assistants (PDAs), notebook PCs, tablet PCs, OA devices, medical devices, and car navigation systems, touch panel sensors are widely used as input means for these displays.

  Touch panel sensors include optical methods, ultrasonic methods, resistive film methods, surface capacitive methods, projection capacitive methods, etc., depending on the position detection method. A capacitance method is preferably used. The resistive film type touch panel sensor has a structure in which two light transmissive electrodes each having a light transmissive conductive layer on a support are used and the light transmissive electrodes are arranged to face each other via a dot spacer. By applying force to one point of the touch panel sensor, the light-transmitting conductive layers contacted each other, and the voltage applied to each light-transmitting conductive layer was measured through the other light-transmitting conductive layer, and the force was applied. Position detection is performed. On the other hand, the projected capacitive touch panel sensor uses one light transmissive electrode having two light transmissive conductive layers or two light transmissive electrodes having one light transmissive conductive layer. Then, the position where the finger is approached is detected from the change in the capacitance between the light-transmitting conductive layers when the finger or the like is approached. The latter has excellent durability because it has no moving parts, and can detect multiple points at the same time. Therefore, the latter is widely used particularly in smartphones and tablet PCs.

  In a projected capacitive touch panel sensor, a sensor unit consisting of a plurality of sensors obtained by patterning a light-transmitting conductive layer on a support can be used for simultaneous detection of multiple points and movement points. Detection is possible. In order to extract the change in capacitance detected by the sensor unit to the outside as an electric signal, all of the sensors included in the light transmissive electrode and a terminal unit including a plurality of terminals provided to extract the electric signal to the outside A peripheral wiring portion including a plurality of peripheral wirings for electrically connecting them is provided between them.

  In the prior art, the light-transmitting conductive layer is generally formed of an ITO (indium-tin oxide) conductive film. However, in recent years, the light-transmitting conductive layer is a light having a mesh-like metal fine line pattern. A transmissive electrode is also disclosed. Among metals, silver is preferable because it has the highest conductivity, and can be obtained with a thin wire having a narrower width and a thinner film thickness than other metals, so that high conductivity can be obtained. As a method for producing a conductive material having a mesh-like metal fine line pattern made of silver, for example, Japanese Unexamined Patent Application Publication No. 2015-133239 (Patent Document 1) includes a mesh-like metal fine wire pattern and a peripheral wiring portion containing silver fine particles. A method of printing ink, a method of performing electroless plating after printing a resin paint containing an electroless plating catalyst, a photoresist layer on a metal layer, forming a resist pattern, and then forming a metal layer It describes that it can be formed by various methods such as a subtractive method for removing by etching and a method using a silver salt photosensitive material.

  A mesh-like fine metal wire pattern formed of silver having high conductivity can provide good conductivity even if the width of the fine metal wire is thin or the thickness of the fine metal wire is thin. When the light transmissive electrodes are bonded to each other, or when the light transmissive electrode having the mesh metal thin line pattern is used as a touch sensor, unintentional disconnection occurs, and the electrode conduction failure or the electrode In some cases, there is a case where conductive flare occurs between the electrodes and conductive flare between the electrodes.

  On the other hand, the electric circuit pattern formed of silver is likely to cause migration, and as a technique for preventing these, Japanese Patent Application Laid-Open No. 2009-188360 (Patent Document 2) describes benzotriazole, a benzotriazole derivative, and a mercapto compound as a metal. A technique for adsorbing as an ion trapping agent is disclosed. In addition, JP-A-2013-144836 (Patent Document 3) describes 2-mercaptobenzothiazole as an example of a vaporizable rust preventive agent contained in a surface treatment agent that imparts discoloration resistance to a silver vapor-deposited surface. Japanese Patent Application Laid-Open No. 2011-241409 (Patent Document 4) discloses a mercapto having a specific structure as a corrosion inhibitor for the purpose of forming a film excellent in discoloration prevention effect and wire bonding characteristics on silver or a silver alloy. Direct current electrolysis is described using an aqueous surface treatment agent solution containing benzothiazole.

Japanese Patent Laying-Open No. 2015-133239 JP 2009-188360 A JP 2013-144836 A JP 2011-241409 A

  The objective of this invention is providing the processing method of the electroconductive material from which the electroconductive flare in an electrode or the electroconductive flare between electrodes is obtained is obtained.

The above object of the present invention is achieved by the following invention.
(1) treating a conductive material having a network-like fine metal wire pattern formed of silver on a support with a surface treatment liquid containing a mercaptobenzothiazole compound represented by the following general formula (I) A method for treating a conductive material.

(In the formula, R ₁ represents hydrogen, a substituted or unsubstituted alkyl group, or halogen, and R ₂ represents an alkali metal, hydrogen, or a substituted or unsubstituted alkyl group.)

  According to the present invention, it is possible to provide a method for producing a conductive material from which a conductive material with improved conductive flare within the electrodes or between the electrodes can be obtained.

Electrode patterns used in the examples

  The conductive material used in the treatment method of the present invention has a network-like fine metal wire pattern formed of silver on a support. Such mesh shapes include triangles such as regular triangles, isosceles triangles and right triangles, squares such as squares, rectangles, rhombuses, parallelograms, trapezoids, (positive) hexagons, (positive) octagons, (positive) tens Examples include a combination of a (positive) n-gon, such as a square, a (positive) icosahedron, a circle, an ellipse, and a star. The mesh shape may be formed by an irregular fine line pattern, and examples thereof include a mesh shape obtained by an irregular geometric shape represented by a Voronoi figure, Delaunay figure, Penrose tile figure, etc. . In addition, in this invention, although a mesh-like metal fine wire pattern is formed with silver, as long as it is less than 10 mass% with respect to silver, other metals, such as gold | metal | money, copper, nickel, aluminum, may be included.

  Regarding the line width and film thickness of the fine lines constituting the above-mentioned mesh-like metal fine line pattern, the line width is 1 to 50 μm in consideration of the visibility (hard visibility) of the fine metal lines, conductivity, light transmittance, and the like. It is preferable that the thickness of the thin wire is 50 μm or less. The pitch of the thin wires is preferably 100 to 1000 μm. The fine line width and pitch of the mesh-like fine metal line pattern are appropriately adjusted according to each application.

  If the thickness of the fine wire constituting the mesh-like metal fine wire pattern is thin, various functional layers such as an adhesive layer and a hard coat layer can be easily provided on the pattern. For example, when a pressure-sensitive adhesive layer is provided on the surface of the metal pattern, such as a touch sensor that bonds two electrodes together or an electromagnetic wave shielding film that is bonded to a window glass, etc. Since it is easy to bond uniformly with less contamination, it is a great advantage that the pattern is thin. Therefore, it is more preferable that the thickness of the fine wire constituting the mesh-like metal fine wire pattern is 0.3 μm or less.

  On the other hand, if the thickness of the thin wire constituting the mesh metal thin wire pattern is thin, unintentional disconnection is likely to occur during the manufacturing process, product handling, or product use. In particular, the present invention works extremely effectively in such a case.

  Next, a method for forming a reticulated metal fine wire pattern (hereinafter also simply referred to as a silver pattern) formed of silver on a support will be described. In the present invention, various methods can be used as a method for forming a silver pattern on a support. For example, a printing method, a photolithography method, a silver salt method using photosensitive silver halide, or the like can be used.

  As a printing method, for example, as disclosed in Japanese Patent Application Laid-Open No. 55-91199, after printing a metallic silver ink or paste by means of screen printing or the like, a method of firing to impart conductivity, an international method, For example, a method of printing a resin paint containing an electroless plating catalyst or the like, and applying electroless silver plating to give a conductive pattern, as disclosed in Japanese Patent Publication No. 04/39138, can be used.

  The photolithographic method is a subtractive method in which a photoresist is coated on a support having a uniform metal silver layer, and after exposure and development, the metal silver layer from which the resist has been peeled is removed by etching to obtain a conductive pattern. A resist containing an electroless plating catalyst as disclosed in JP-A-11-170421 is coated on a substrate, exposed and developed to remove unexposed portions of the resist, and then electroless silver-plated. It is possible to use an additive method for obtaining a conductive pattern.

  The silver salt system using photosensitive silver halide is disclosed in International Publication No. 04/007810 pamphlet, Japanese Patent Application Laid-Open No. 2003-77350, Japanese Patent Application Laid-Open No. 2005-250169, and Japanese Patent Application Laid-Open No. 2007-188655. And those using chemically developed silver as disclosed in International Publication No. 2001/512276 pamphlet and Japanese Patent Application Laid-Open No. 2004-221564 can be used. In the method using chemically developed silver, the exposed portion of silver halide is made conductive by applying electroless plating using the chemically developed silver produced by reduction by the developing agent present in the developer as the catalyst core. There is also.

  The method using the silver salt diffusion transfer method is called a physical development nucleus layer on a support, a catalyst nucleus layer for the silver complex to be reduced by a developing agent to become metallic silver, and a silver halide emulsion layer thereon. The provided material is used (the silver halide photographic emulsion layer may be coated on another support). In the development process, a compound (silver halide solvent) that dissolves silver halide is allowed to act in addition to the developing agent. When this material is exposed and developed, when a negative-type silver halide emulsion is used, the silver halide in the exposed portion is converted into chemically developed silver and remains in the silver halide emulsion layer. On the other hand, the unexposed silver halide is dissolved by the silver halide solvent added in the developer to form a silver complex that moves and diffuses to the physical development nucleus layer on the support, where it is reduced by the developing agent. Thus, conductive metallic silver is deposited. Thereafter, the emulsion layer containing chemically developed silver at the exposed site is removed by washing off.

  Among the methods for forming a silver pattern on a support, a method using a silver salt diffusion transfer method is particularly preferred. When the silver salt diffusion transfer method is used, a uniform silver pattern having a film thickness of 0.3 μm or less can be easily and stably produced. Further, the silver pattern obtained by the method using the silver salt diffusion transfer system is almost formed only from metallic silver, and extremely high conductivity can be obtained even if the film thickness is 0.3 μm or less. Furthermore, a silver pattern having a line width of 15 μm or less is preferably used in order to achieve the high light transmittance required for sensor electrodes for touch panels and the excellent visibility (hard visibility) of the silver pattern. The salt diffusion transfer method is preferable because a uniform and high-definition pattern is formed.

  Hereinafter, the silver salt diffusion transfer method, which is the most preferable method for forming a silver pattern, will be described in detail. As a representative form, a conductive material precursor having at least a physical development nucleus layer and a silver halide emulsion layer on a support is allowed to act in an alkaline developer containing a soluble silver salt forming agent and a reducing agent. A method for forming a silver pattern on the support will be described.

  The conductive material precursor described above has at least a physical development nucleus layer and a silver halide emulsion layer on the support in this order from the side closer to the support. Further, the non-photosensitive layer is the outermost layer farthest from the support and / or an intermediate layer between the physical development nucleus layer and the silver halide emulsion layer, or an undercoat layer between the support and the physical development nucleus layer. You may have as.

As the physical development nuclei contained in the physical development nuclei layer, fine particles (having a particle size of about 1 to several tens of nm) made of heavy metals or sulfides thereof are used. Examples of such fine particles include colloids such as gold and silver, metal sulfides obtained by mixing sulfides with water-soluble salts such as palladium and zinc, and the like. The physical development nucleus layer containing these fine particles can be provided on a support on which the above-described undercoat layer is formed, for example, by a coating method or an immersion treatment method. From the viewpoint of production efficiency, a coating method is preferably used. The content of physical development nuclei in the physical development nuclei layer is suitably about 0.1 to 10 mg per m ^{2 in} terms of solid content.

  The physical development nucleus layer of the conductive material precursor can also contain a water-soluble polymer compound. When the water-soluble polymer compound is used, the addition amount is preferably about 0 to 500% by mass with respect to the physical development nucleus. Examples of the water-soluble polymer compound include gum arabic, cellulose, sodium alginate, polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, a copolymer of acrylamide and vinyl imidazole, and the like.

  The physical development nucleus layer that the conductive material precursor has may also contain a crosslinking agent. Examples of the crosslinking agent include inorganic compounds such as chromium alum, aldehydes such as formaldehyde, glyoxal, malealdehyde, and glutaraldehyde, N-methylol compounds such as urea and ethylene urea, mucochloric acid, and 2,3-dihydroxy. Aldehyde equivalents such as -1,4-dioxane, compounds having an active halogen such as 2,4-dichloro-6-hydroxy-s-triazine salt and 2,4-dihydroxy-6-chloro-triazine salt, Divinyl sulfone, divinyl ketone, N, N, N-triacryloyl hexahydrotriazine, compounds having two or more active three-membered ethyleneimino groups and epoxy groups in the molecule, and dimers as polymer hardeners One or more of various compounds such as aldehyde starch can be usedAmong the crosslinking agents, dialdehydes such as glyoxal, glutaraldehyde, 3-methylglutaraldehyde, succinaldehyde, and adipaldehyde are preferable, and glutaraldehyde is more preferable. The crosslinking agent is preferably from 0.1 to 30% by mass, particularly preferably from 1 to 20% by mass, based on the aforementioned water-soluble polymer compound.

  The physical development nucleus layer is preferably formed by applying a coating solution containing the above-described physical development nucleus, a water-soluble polymer compound, a crosslinking agent and the like on a support. For application of the coating solution, for example, application methods such as dip coating, slide coating, curtain coating, bar coating, air knife coating, roll coating, gravure coating, spray coating, and the like can be used.

  A silver halide emulsion layer is provided on the above-described physical development nucleus layer or a non-photosensitive layer provided on a physical development nucleus layer described later. Techniques used in silver halide photographic films, photographic papers, printing plate-making films, emulsion masks for photomasks, etc. relating to silver halide can be used as they are.

  For formation of silver halide emulsion grains contained in the silver halide emulsion layer, Research Disclosure Item 17643 (December 1978) and 18716 (November 1979), 308119 (such as forward mixing, reverse mixing, and simultaneous mixing) are used. (December 1989) can be used. Of these, the so-called controlled double jet method, which is one of the simultaneous mixing methods and keeps pAg in the liquid phase in which the grains are formed, is preferable from the viewpoint of obtaining silver halide emulsion grains having a uniform particle diameter. In the conductive material precursor of the present invention, the preferable average grain size of the silver halide emulsion grains is preferably 0.25 μm or less, and particularly preferably 0.05 to 0.2 μm. There is a preferable range for the halide composition contained in the silver halide emulsion, and it is preferable to contain 80 mol% or more of chloride, and particularly preferably 90 mol% or more of chloride.

  In the production of silver halide emulsions, in the process of silver halide grain formation or physical ripening, sulfites, lead salts, thallium salts, rhodium salts or complex salts thereof, iridium salts or complex salt salts of group VIII metal elements, etc. Or a complex salt thereof may coexist. Further, it can be sensitized by various chemical sensitizers, and methods commonly used in the art such as sulfur sensitization method, selenium sensitization method and noble metal sensitization method can be used alone or in combination. In the conductive material precursor used in the present invention, the silver halide emulsion can be dye-sensitized as necessary.

The silver halide emulsion layer preferably contains a binder component together with the above-described silver halide emulsion. As such a binder, gelatin is suitable. The ratio between the amount of silver halide contained in the silver halide emulsion layer and the amount of binder is preferably such that the mass ratio of silver halide (in terms of silver) to gelatin (silver / gelatin) is 1.2 or more, more preferably Is 1.5 or more. The amount of silver halide contained in the silver halide emulsion layer is preferably ² to 10 g / m ² in terms of silver.

  The silver halide emulsion layer can further contain known photographic additives for various purposes. These are described in Research Disclosure Item 17643 (December 1978) and 18716 (November 1979), 308119 (December 1989) or cited.

  In the conductive material precursor, a non-photosensitive layer can be provided between the silver halide emulsion layer and the physical development nucleus layer or on the silver halide emulsion layer. These non-photosensitive layers are layers containing a water-soluble polymer compound as a main binder. The water-soluble polymer compound here means that it easily swells with a developer and develops up to a silver halide emulsion layer or a physical development nucleus layer located below the non-photosensitive layer (side closer to the support). Any liquid can be selected as long as it can easily penetrate the liquid.

  Specifically, gelatin, albumin, casein, polyvinyl alcohol, or the like can be used. Particularly preferred water-soluble polymer compounds are proteins such as gelatin, albumin and casein. In order to sufficiently obtain the effects of the present invention, the amount of the binder in the non-photosensitive layer is preferably in the range of 20 to 100% by mass, particularly 30 to 80% by mass, based on the total amount of binder in the silver halide emulsion layer. % Is preferred.

  These non-photosensitive layers may be added to known photographic additives as described in Research Disclosure Item 17643 (December 1978) and 18716 (November 1979), 308119 (December 1989), if necessary. An agent can be included. Further, the film can be hardened with a crosslinking agent as long as the peeling of the silver halide emulsion layer after the treatment is not prevented.

The conductive material precursor preferably contains a non-sensitizing dye or pigment having an absorption maximum in the photosensitive wavelength region of the silver halide emulsion layer as a halation for improving image quality or an irradiation inhibitor. The antihalation agent is preferably provided with the above-described undercoat layer or physical development nucleus layer, or an intermediate layer provided as necessary between the physical development nucleus layer and the silver halide emulsion layer, or a support. It can be contained in the backing layer. The irradiation inhibitor is preferably contained in the silver halide emulsion layer. The content of the non-sensitizing dye or pigment can vary widely as long as the desired effect is obtained. For example, when it is contained in the backing layer as an antihalation agent, the content is about 20 mg to about 1 g per m ² . The range is desirable, and the absorbance at the maximum absorption wavelength of the silver halide emulsion is preferably 0.5 or more.

  Next, a method for drawing a silver pattern using the above-described conductive material precursor will be described.

  In drawing a silver pattern, the conductive material precursor is exposed. Specifically, the silver halide emulsion layer contained in the conductive material precursor is exposed imagewise (desired silver pattern). As an exposure method, a transparent original having a desired pattern and the silver halide emulsion layer are adhered. Or a method of scanning and exposing a desired pattern using various laser beams. In the method of exposing with laser light, for example, a blue semiconductor laser (also referred to as a violet laser diode) having an oscillation wavelength of 400 to 430 nm can be used.

  Next, development processing using a silver salt diffusion transfer developer of a conductive material precursor will be described. The silver halide emulsion layer of the conductive material precursor exposed as described above undergoes physical development by processing with a silver salt diffusion transfer developer, and has no latent image nuclei that can be developed. Silver is dissolved by a soluble silver complex salt forming agent to form a silver complex salt, which is reduced on the physical development nuclei to deposit metallic silver, and for example, a mesh-patterned silver thin film can be obtained. On the other hand, silver halide having latent image nuclei that can be developed by exposure is chemically developed in the silver halide emulsion layer to become blackened silver. After development, unnecessary silver halide emulsion layers (including blackened silver), intermediate layers, protective layers and the like are removed, and a patterned silver thin film is exposed on the surface.

  The layer provided on the physical development nucleus layer such as a silver halide emulsion layer after development is removed by washing with water or a method of transferring and peeling to a release paper or the like. There are two methods for removing the water washing: a method of removing hot water using a scrubbing roller or the like while jetting it with a nozzle or the like, and a method of removing hot water by jetting with a nozzle or the like. In addition, the method of transferring and peeling with a release paper or the like is to squeeze the excess alkali solution (silver complex diffusion transfer developer) on the silver halide emulsion layer in advance with a roller or the like, and remove the silver halide emulsion layer and the release paper. In this method, the silver halide emulsion layer and the like are transferred from a plastic resin film to a release paper and peeled off. As the release paper, water-absorbing paper or non-woven fabric, or paper having a water-absorbing void layer formed of fine pigment such as silica and binder such as polyvinyl alcohol on the paper is used.

  The developer used for the development processing described above is an alkaline solution containing a soluble silver complex salt forming agent and a reducing agent. The soluble silver complex salt forming agent is a compound that dissolves silver halide to form a soluble silver complex salt, and the reducing agent is a compound for reducing the soluble silver complex salt to deposit metallic silver on the physical development nucleus. .

  Soluble silver complex forming agents contained in the developer include thiosulfates such as sodium thiosulfate and ammonium thiosulfate, thiocyanates such as sodium thiocyanate and ammonium thiocyanate, and sulfites such as sodium sulfite and potassium hydrogen sulfite. Salts, oxazolidones, 2-mercaptobenzoic acid and derivatives thereof, cyclic imides such as uracil, alkanolamines, diamines, mesoionic compounds described in JP-A-9-171257, US Pat. No. 5,200,294 Thioethers, 5,5-dialkylhydantoins, alkylsulfones, and others described in the specification, “The Theory of the Photographic Process (4th edition, p474-475)”, T. et al. H. Examples include compounds described in James. These soluble silver complex salt forming agents can be used alone or in combination.

  The reducing agent contained in the developer is a known development in the field of photographic development as described in Research Disclosure Item 17643 (December 1978) and 18716 (November 1979), 308119 (December 1989). The main drug can be used. For example, polyhydroxybenzenes such as hydroquinone, catechol, pyrogallol, methylhydroquinone, chlorohydroquinone, ascorbic acid and its derivatives, 1-phenyl-4,4-dimethyl-3-pyrazolidone, 1-phenyl-3-pyrazolidone, 1- Examples include 3-pyrazolidones such as phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone, paramethylaminophenol, paraaminophenol, parahydroxyphenylglycine, paraphenylenediamine, and the like. These reducing agents can be used alone or in combination.

  The content of the soluble silver complex salt forming agent is preferably 0.001 to 5 mol, more preferably 0.005 to 1 mol, per liter of the developer. The content of the reducing agent is preferably from 0.01 to 1 mol, more preferably from 0.05 to 1 mol, per liter of the developer.

  The pH of the developer is preferably 10 or more, and more preferably 11-14. In order to adjust to a desired pH, an alkali agent such as sodium hydroxide or potassium hydroxide, or a buffering agent such as phosphoric acid or carbonic acid is contained alone or in combination. The developer preferably contains a preservative such as sodium sulfite or potassium sulfite.

  Application of the developer described above may be a method of immersing the exposed conductive material precursor in the developer (immersion method) or a method of applying the developer to the conductive material precursor (coating method). Good. In the dipping method, for example, the exposed conductive material precursor is conveyed while dipped in a large amount of developer stored in a tank, and the coating method is, for example, the developer on the silver halide emulsion layer side. About 40 to 120 ml per square meter. Specific examples of the dipping method include a processing method and a processing apparatus as disclosed in JP-A-2006-190535, and according to such a method, a surface on which a silver pattern is formed is conveyed. Since development proceeds in a non-contact state without being in contact with a roller or the like, the silver pattern is not easily broken, which is preferable. The application temperature of the developer is preferably 2 to 30 ° C, more preferably 10 to 25 ° C. The application time of the developer is suitably about 20 seconds to 3 minutes.

  In the method for treating a conductive material of the present invention, the conductive material having a network-like fine metal wire pattern formed as described above is a surface containing a mercaptobenzothiazole compound represented by the following general formula (I) Processing is performed with a processing solution.

In the formula, R ₁ represents hydrogen, a substituted or unsubstituted alkyl group, or halogen, and R ₂ represents an alkali metal, hydrogen, or a substituted or unsubstituted alkyl group.

  Specific examples of the above-described mercaptobenzothiazole compound are shown below.

  In the present invention, mercaptobenzothiazole, mercaptobenzothiazole sodium salt, and mercaptobenzothiazole potassium salt are particularly suitable.

  The surface treatment method is not particularly specified. For example, a conductive material on which a network-like metallic silver fine line pattern is drawn is immersed in a solution containing a mercaptobenzothiazole compound represented by the general formula (I). And a method of applying a solution containing a mercaptobenzothiazole compound represented by the general formula (I) to a conductive material on which a network-like metal silver fine line pattern is drawn. 10-50 degreeC is preferable and, as for the solution temperature (processing temperature) at the time of immersion or application | coating, 20-40 degreeC is more preferable. The treatment time is preferably 10 seconds or longer, more preferably 30 seconds or longer.

  Examples of the solvent contained in the surface treatment liquid containing the mercaptobenzothiazole compound represented by the general formula (I) include water, alcohols such as ethanol, ketones such as acetone, ethers such as tetrahydrofuran, methyl, and the like. Examples thereof include cellosolve, N, N-dimethylformamide, dimethyl sulfoxide and the like.

  In the present invention, the content of the mercaptobenzothiazole compound contained in the surface treatment liquid is preferably 0.01 to 20 g, more preferably 0.05 to 5 g, per liter of the surface treatment liquid.

  The above-described surface treatment liquid can contain other compounds as necessary. For example, an alkali, an acid, a buffering agent, or the like for adjusting the pH of the surface treatment solution can be contained. When the surface treatment liquid uses water as a solvent, the pH of the surface treatment liquid is preferably 8 or more. Furthermore, the surface treatment liquid can also contain an antifoaming agent, an antiseptic, an enzyme, a surfactant and the like. Drying after the surface treatment can be performed by any method such as using warm air from a film dryer. It can also be washed with tap water or pure water before drying.

  Moreover, when providing an adhesive layer on a metal silver fine wire pattern like the touchscreen sensor which bonds two transparent electrodes, or the electromagnetic wave shield film bonded to a window glass, it does not immerse in the surface treatment liquid mentioned above. Also, a coating solution for forming a pressure-sensitive adhesive layer in which the mercaptobenzothiazole compound represented by the general formula (I) is dispersed is prepared, and the coating solution is used as a surface treatment solution, and the coating solution is applied onto a metal silver fine wire pattern. However, it can also be processed.

  In the present invention, as described in Japanese Patent Application Laid-Open No. 2008-34366, post-treatment (hereinafter referred to as “half-width of 2θ = 38.2 °” in the X-ray diffraction method of silver pattern is 0.41 or less) , Simply referred to as post-treatment), it is preferable to use the surface treatment of the present invention in combination.

  Although the above-described post-treatment improves conductivity, disconnection or the like during production or use is more likely to occur, but disconnection can be prevented by using the surface treatment of the present invention in combination. Although such post-treatment can be performed either before or after the surface treatment of the present invention, the post-treatment is to prevent disconnection that may occur during the post-treatment process, for example, transport of the treatment apparatus. Is preferable.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but it is needless to say that the present invention is not limited by this description.

Example 1
As a support, a polyethylene terephthalate film having a total light transmittance of 90% and a thickness of 100 μm, which was subjected to easy adhesion processing with a layer containing vinylidene chloride, was used. Before the physical development nucleus layer was applied, an undercoat layer containing 500 mg / m ^{2 of} gelatin was applied to the film and dried.

  Next, a palladium sulfide sol solution was prepared as follows, and a physical development nucleus solution was prepared using the obtained sol.

<Preparation of palladium sulfide sol>
Liquid A Palladium chloride 5g
Hydrochloric acid 40mL
Distilled water 1000mL
B liquid sodium sulfide 8.6g
Distilled water 1000mL
Liquid A and liquid B were mixed with stirring, and 30 minutes later, the solution was passed through a column filled with an ion exchange resin to obtain palladium sulfide sol.

<Physical development nuclei solution composition / 1 m ² per>
The palladium sulfide sol 0.4mg
0.08 mL of 2% glutaraldehyde solution
10 mass% SP-200 aqueous solution 0.5 mg
(Nippon Shokubai Co., Ltd. polyethyleneimine; average molecular weight 10,000)

This physical development nuclei solution was applied on the undercoat layer so that palladium sulfide was 0.4 mg / m ² in solid content, and dried.

Subsequently, a backing layer having the following composition was applied to the surface opposite to the side on which the physical development nucleus layer was applied.
<Undercoat layer composition / per 1 m ² >
2g of gelatin
Amorphous silica matting agent (average particle size 5μm) 20mg
Dye 1 200mg
Surfactant (S-1) 400mg

  Subsequently, an intermediate layer, a silver halide emulsion layer, and an outermost layer having the following composition were coated on the physical development nucleus layer in order from the side closer to the support. The silver halide emulsion was prepared by a general double jet mixing method for photographic silver halide emulsions. This silver halide emulsion was prepared with 95 mol% of silver chloride and 5 mol% of silver bromide, and an average grain size of 0.15 μm. The silver halide emulsion thus obtained was subjected to gold sulfur sensitization using sodium thiosulfate and chloroauric acid according to a conventional method. The silver halide emulsion thus obtained contains 0.5 g of gelatin per gram of silver.

<Intermediate layer composition / per 1 m ² >
Gelatin 0.5g
Surfactant (S-1) 5mg

<Silver halide emulsion layer composition / 1m ² per>
Gelatin 1.0g
Silver halide emulsion 6.0g silver equivalent 1-phenyl-5-mercaptotetrazole 3.0mg
Surfactant (S-1) 20mg

<Outermost layer composition / per 1 m ² >
1g of gelatin
Amorphous silica matting agent (average particle size 3.5μm) 10mg
Surfactant (S-1) 10mg

  The conductive material precursor thus obtained was exposed by closely contacting a transparent original having the pattern of FIG. 1 with a contact printer using a mercury lamp as a light source. In the pattern of FIG. 1, the silver mesh pattern part (conductive part) a is a unit figure having a line width of 10 μm and a fine line interval of 300 μm made of a square mesh, and seven a are congruent figures. b is an electrode terminal portion, and c is a non-image portion (non-conductive portion). The exposure amount was such that the mesh fine line width of the conductive material was the same as the fine line width of the transparent original.

  Thereafter, the exposed conductive material precursor was immersed in the following developer at 20 ° C. for 60 seconds, and then the silver halide emulsion layer, intermediate layer, outermost layer and backing layer were removed by washing with warm water at 40 ° C. And dried. A conductive material having a silver thin film formed in a mesh pattern was obtained from the exposed sample. When the fine line width and pitch of the obtained silver pattern image of FIG. 1 were confirmed with an optical microscope, the fine line width and pitch of the exposure mask were reproduced. Moreover, it was 0.15 micrometer when the film thickness of the thin wire | line part was investigated with the confocal microscope (Lasertec company make, Optics C130).

<Diffusion transfer developer composition>
Potassium hydroxide 40g
Hydroquinone 28g
1-phenyl-3-pyrazolidone 3g
125g potassium sulfite
24g of N-methylethanolamine
Potassium bromide 2g
Bring the total volume to 1000 mL with water.
Adjust to pH = 12.2.

  The electrical resistance between the electrode terminals of the conductive material formed with the silver pattern of FIG. 1 obtained as described above was measured with a tester (part b in FIG. 1). The outermost terminal was 1, the innermost terminal was 7, and the electrical resistance between the electrode terminals of terminals 1 to 7 was measured with a tester. These results are shown in Table 1 (before bonding in the table).

  The conductive material on which the silver pattern of FIG. 1 obtained as described above was formed was immersed in the following surface treatment solution at 30 ° C. for 60 seconds. Thereafter, it was washed with warm water at 35 ° C. for 30 seconds and dried with warm air at 60 ° C. for 2 minutes using a film dryer.

<Surface treatment solution>
Sodium hydroxide 1.4g
Mercaptobenzothiazole compound (1) 0.7 g
Dipotassium hydrogen phosphate 8.3g
85% by mass phosphoric acid 3.7 g
Bring the total volume to 1000 mL with water.

  The surface-treated conductive material on which the silver pattern of FIG. 1 was formed was post-treated by being immersed in a 3% by mass aqueous sodium chloride solution at 60 ° C. for 60 seconds. Thereafter, it was washed with warm water at 35 ° C. for 30 seconds and dried with warm air at 60 ° C. for 2 minutes using a film dryer.

  A transparent adhesive sheet for optics (LUCIACS (registered trademark) CS9622T manufactured by Nitto Denko Corporation) is applied to the conductive material on which the silver pattern of FIG. It adjusted to 5 MPa / m, pressurized while conveying at 1 m / min, and bonded together on the silver pattern. At this time, in the silver pattern of FIG. 1, the optical transparent adhesive sheet was bonded so that the terminal portion b was not covered and the lowermost electrode to the uppermost electrode were covered. After the conductive material with the adhesive sheet bonded thereto was stored at 60 ° C. and 85% RH for 200 hours, the electrical resistance between the electrode terminals of the conductive material was measured with a tester in the same manner as before bonding. These results are shown in Table 1 (after bonding in the table).

(Example 2)
A conductive material was prepared in the same manner as in Example 1 except that the mercaptobenzothiazole compound (1) contained in the surface treatment liquid was changed to the mercaptobenzothiazole compound (2), and evaluated in the same manner as in Example 1. Carried out. These results are shown in Table 1.

(Example 3)
A conductive material was prepared in the same manner as in Example 1 except that the mercaptobenzothiazole compound (1) contained in the surface treatment liquid was changed to the mercaptobenzothiazole compound (3). Carried out. These results are shown in Table 1.

(Comparative Example 1)
A conductive material was prepared in the same manner as in Example 1 except that the treatment with the surface treatment liquid was not performed, and the evaluation was performed in the same manner as in Example 1. These results are shown in Table 1.

(Comparative Example 2)
A conductive material was prepared in the same manner as in Example 1 except that the mercaptobenzothiazole compound (1) in the surface treatment solution was changed to 2-amino-4,6-dimercaptopyrimidine. Carried out. These results are shown in Table 1.

(Comparative Example 3)
A conductive material was prepared in the same manner as in Example 1 except that the mercaptobenzothiazole compound (1) in the surface treatment solution was changed to 2-mercaptobenzimidazole, and evaluation was performed in the same manner as in Example 1. These results are shown in Table 1.

(Comparative Example 4)
A conductive material was prepared in the same manner as in Example 1 except that the mercaptobenzothiazole compound (1) in the surface treatment solution was changed to 1-phenyl-5-mercaptotetrazole, and evaluation was performed in the same manner as in Example 1. These results are shown in Table 1.

  From the results in Table 1, the effectiveness of the present invention can be understood.

  As is clear from the above results, according to the present invention, it is possible to obtain a method for treating a conductive material that can provide a conductive material with improved conductive flare within the electrodes or between the electrodes. it can.

  The treatment method of the conductive material of the present invention of the present invention can be a promising surface treatment method for production of electromagnetic shielding materials such as various displays and windows and various transparent electrodes for touch panels.

a. Silver mesh pattern part (conductive part)
b. Electrode terminal part c. Non-image part (non-conductive part)

Claims (1)

A conductive material having a reticulated metal fine wire pattern formed of silver on a support is treated with a surface treatment solution containing a mercaptobenzothiazole compound represented by the following general formula (I). A method for treating a conductive material.
(In the formula, R ₁ represents hydrogen, a substituted or unsubstituted alkyl group, or halogen, and R ₂ represents an alkali metal, hydrogen, or a substituted or unsubstituted alkyl group.)